<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style>
	.test {
		width: 400px;
		background-color: red;
		height: 50px;
	}
	</style>
</head>
<body>

	<div class="test">
		
	</div>

	<script>

		/*function NJ() {

			this.name = "nj";
		}

		var nj = NJ();

		nj2 = new NJ();

		console.log(typeof nj);
		console.log(typeof nj2);*/
		
		/*var a;
		console.log(a === undefined);

		var undefined;

		undefined = 1;

		console.log(a === undefined);*/

		/*function p(arr) {
			var i, l = arr.length;
			for(i=0; i<l; i++) {
				setTimeout(function() {
					console.log(arr[i])
				}, 200);
			}
		}

		p([1, 2, 3]);*/

		// function ppp(arr) {
		// 	var i = 0, len = arr.length, timer;
		// 	timer = setInterval(function() {
		// 		if (i >= len-1) {
		// 			clearInterval(timer);
		// 		}
		// 		console.log(arr[i]);
		// 		i++;
		// 	}, 200);
		// }

		// ppp([1, 2, 3]);
	</script>
	
</body>
</html>